Skin-contacting articles, such as gloves, particularly medical gloves, are commonly used as a protective barrier against the contamination of the user by chemicals and body fluids containing microorganisms including bacteria and/or viruses and the like. As such, these gloves and other skin-contacting articles are manufactured in such a way that they are entirely impermeable to the contaminants or microorganisms during use. However, medical gloves are typically extremely thin, manufactured from soft elastomeric materials such as natural or synthetic rubbers and may puncture or rupture during use, allowing microorganisms to pass through the discontinuity in the glove.
One approach to this problem has been the application of antimicrobial coatings to the elastomeric articles. For example, U.S. Pat. No. 4,853,978 (Stockum) discloses a natural rubber surgical glove having an inner coating containing the cationic antimicrobial agents chlorhexidine gluconate (CHG) or polyhexamethylene biguanide hydrochloride (PHMB). Cross-linked cornstarch is included in the inner coating as an anti-blocking agent, which is also said to affix the CHG and PHMB in place and allow their slow release during perspiration. However, the use of cross-linked cornstarch is not compatible with the trend towards powder-free medical environments.
U.S. Pat. No. 5,089,205 (Huang) discloses natural latex gloves having an inner lubricant layer containing chlorhexidine diacetate. Again, powdered starch is disclosed as an anti-blocking agent. Although the patent teaches modifying the chlorhexidine with an anionic or nonionic surfactant to render it compatible with anionic components of the gloves, no mention is made of the effect of the surfactant on antimicrobial efficacy since the anionic or non-ionic surfactant (which has both anionic and cationic counter parts that have equivalent charges) will clearly neutralize the chlorhexidine cationic antimicrobial agent.
U.S. Pat. No. 5,133,090 (Modak et al.) discloses a latex glove having an inner coating of chlorhexidine and a lubricating agent, such as zinc oxide, hydroxycellulose or corn starch. Corn starch can be used provided it has been modified with a surfactant to block adsorption sites for the chlorhexidine. Again use of corn starch does not result in a powder free surgical glove.
U.S. Pat. No. 5,483,697 (Fuchs) discloses a double-layer latex glove having an inner layer, an outer layer sealing a middle layer comprising an antimicrobial agent in the form of a solution, which may be mixed with a hydrogel. The hydrogel is said to physically block or plug holes that form in the inner and outer layers. Examples of hydrogels include corn starch and derivatives of cellulose. No mention is made of the effect of the hydrogel on the efficacy of the antimicrobial agent. The antimicrobial agent is not delivered to the hand of the user killing any germs present, rather guards against any microbes present in a sharp instrument when the outer surface of the glove is breached. Clearly, the kill time of the microbes becomes an extremely important factor to produce effective kill since the outer glove breach occurs in a short time frame.
U.S. Pat. No. 5,570,475 (Nile et al.) discloses a surgeon's glove having a polymeric donning layer disposed thereon comprising a polymer of specific repeating units. The polymeric layer preferably has raised domains. No mention is made of any antimicrobial agent or the potential effect of the polymer layer on its efficacy.
U.S. Pat. No. 6,391,409 (Yeh et al.) discloses a powder free nitrile-coated natural rubber glove having an intermediate layer comprised of a synthetic rubber and nitrile rubber. The intermediate layer is said to aid donning and prevent self-sticking of the inner glove surfaces. No mention is made of any antimicrobial agent or the potential effect of the intermediate layer on its efficacy.
U.S. Pat. No. 6,378,137 (Hassan et al) discloses a powder-free polymeric medical glove having an outer side silicone-treated surface and an inner side bonded to anti-blocking layer formed from a polymer/copolymer, a high density polyethylene particle, and a wax, the anti-blocking layer coated with a layer of silicone emulsion. No mention is made of any antimicrobial agent or the potential effect of the anti-blocking layer on its efficacy.
U.S. Pat. No. 7,032,251 (Janssen) discloses an elastomeric article having a donning layer comprising a polymeric coating cross-linked with a polyamine epichlorohydrin crosslinking agent. The polymeric coating may comprise cellulose derivatives. No mention is made of any antimicrobial agent or the potential effect of the polymeric coating on its efficacy.
U.S. Patent Publication No. 2003/0204893 (Wang et al.) discloses an elastomeric glove having a preparation disposed on the interior surface of the glove comprising an acidic antimicrobial substance and buffer that resists pH change. The preparation may also comprise thickeners, which include cellulose derivatives. No mention is made of the tackiness or blocking properties of the preparation or the effect of the thickeners on the efficacy of the antimicrobial agent.
U.S. Patent Publication No. 2004/0115250 (Loo et al.) discloses an elastomeric glove having a moisturizing film comprising glycerol and a botanical extract, such as aloe vera and chamomile. The film may also comprise an anti-blocking wax. No mention is made of any antimicrobial agent or the potential effect of the wax on its efficacy.
U.S. Patent Publication No. 2005/0081278 (Williams) discloses an elastomeric glove having a dried lotion coating on the inside skin-contacting surface comprising a film-forming compound and an oil-based emollient. Film forming compounds include polyurethane, acrylonitrile, neoprene, acrylic latex styrene butadiene rubber and polyisoprene. Antimicrobial agents may be present in the coating, but only in amounts sufficient to act as preservatives. No mention is made of the tackiness of the coating, which will lead to blocking of the glove interior surfaces or the efficacy of the antimicrobials within the coating.
U.S. Patent Publication No. 2005/0112180 (Chou) discloses an elastomeric glove having a first layer comprising an antimicrobial agent and a second hand-contacting layer configured to resist penetration by the antimicrobial agent. The interior surface of second layer may be provided with a preparation comprising one or more of a second antimicrobial agent, a buffer, a moisturizer, a soothing agent and a thickener. No mention is made of the tackiness of the second layer preparation or its antimicrobial efficacy.
U.S. Patent Publication No. 2006/0059604 (Lai et al.) and U.S. Pat. No. 6,709,725 (Lai et al.) disclose latex gloves coated with a non-tacky aqueous polymeric emulsion comprising a film-forming polymer or copolymer, a wax, a surfactant and a hardness modifier. No mention is made of any antimicrobial agent or the potential effect of the polymeric emulsion on its efficacy.
U.S. Patent Publication No. 2006/0070167 (Eng et al.) discloses a rubber glove having a dried coating of an emulsified hand-friendly mixture comprising a water-soluble humectant moisturizer, a water-insoluble occlusive moisturizer, a water-soluble surfactant, and a water-soluble lubricant. The coating mixture may also contain an antimicrobial agent. The coating is said to be inherently non-tacky and non-blocking due to the fine dispersion of the water insoluble occlusive moisturizer within the dried coating and the coating is said to improve donning of the glove. No mention is made of the effect of the dried coating on the efficacy of the antimicrobial agent.
U.S. Patent Publication No. 2007/0104766 (Wang et al.) discloses a powder-free elastomeric article having a surface coating comprising an antimicrobial agent, hydrophilic film-forming polymer and a hydrophobic component. The non-volatile water-soluble antimicrobial agent is incorporated in a controlled-release matrix comprising a blend of a hydrophilic polymer and a hydrophobic component. The controlled-release matrix/blend requirements include: compatibility with the antimicrobial agent, formation of a reservoir of antimicrobial agent, coating film flexibility and lower water-solubility of the matrix/blend than that of the antimicrobial agent. The hydrophilic polymers include cellulosic polymers. The hydrophilic polymer is believed to provide a reservoir for the antimicrobial agent, while the hydrophobic component is believed to improve the film's flexibility through its plasticizing effect. The balance of hydrophilicity and hydrophobicity in the coating film is said to control the release of the antimicrobial agent. No mention is made of the tackiness of the surface coating.
Thus, there remains a need for powder-free elastomeric articles, such as medical gloves, which exhibit good antimicrobial and anti-blocking properties.